Charging device for internal combustion engines



M. MALLORY Dec. 5, 1939.

CHARGING DEVICE FOR INTERNAL COMBUSTION ENGINES Filed Nov. 29, 1957.

Patented Dec. 5, 1939 UNITED STATES PATENT OFFICE CHARGING DEVICE FOR INTERNAL COM- BUSTION ENGINES Marion Mallory, Detroit, Mich.

Application November 29, 1937, Serial No. 177,143

9 Claims.

This invention relates to the charging of internal combustion engines with a view to operating With greater efficiency, especially at intermediate speeds or part loads.

It is well known that a small engine operates much more efliciently than a larger engine under the same load, because the throttle is open wider and there is higher compression in the cylinders. For example, a car having a small engine may, under average conditions, run with the throttle more than half way open when the speed is 30 miles per hour.

The volume of the charge is great enough in proportion to the cylinder capacity to insure a high compression and the car may run 30 miles on a gallon of gasoline.

the other hand, if the car is equipped with a large engine, the throttle will be open much less than half way at 30 miles per hour, the compression will be comparatively low and the car will run perhaps less than 20 miles on a gallon of gasoline.

In all engines, and more especially in those having a carburetor and throttle to control the charge for different speeds, the emciency drops rapidly as the throttle is moved toward closed.

position.

To satisfy the popular demand, however, it is necessary to provide an engine large enough to have suflicient reserve power to insure quick acceleration, high speed and good performance The object of this invention is to provide a' in climbing hills.

charging device which operates in such a manner that all of the cylinders deliver full power when the throttle is nearly wide open, but when the throttle is only part way open, say less than half way, most of the power is delivered from one half of the cylinders, While the other half receive a charge of air or very lean mixture containing barely enough fuel to ignite.

Thus at intermediate speeds and part load, the operation is like that of a small engine.

The throttle buretor.

In all engines using two manifolds,

each bank of cylinders is balanced; that is, the

cylinders of each bank fire at even intervals, so

that if one bank is cut out, the other bank is still balanced.

The construction of the invention will be more particularly described in connection with the ac,- companying drawing, in which Fig. 1 is a vertical transverse section through the engine intake and the charging means therefor.

Fig. 2 is a fragmentary section taken on the line 2-2 of Fig. 1.

As shown in the drawing, the manifold 5 is adapted to supply a charge to one bank of cylinders and the manifold 6 is adapted to supply a charge to the other bank. The mixing chamber 1 leading to the manifold 5 has an air inlet 8, venturi 9, fuel inlet nozzle l0 and throttle valve II. The mixing chamber l2 leading to the manifold 6 has an air inlet I3, venturi l4, fuel inlet nozzle l5 and throttle valve I6. The throttle valves H and I6 are mounted on a common shaft H, which is provided with the usual crank I8 adapted to be operated from the accelerator pedal.

A fuel line 19 leads from the carburetor bowl 20 to the nozzle l0 and another fuel line 2| leads from the bowl to the nozzle l 5. A line 22 leads to the idle jets for both chambers I and I2. Each idle jet has an orifice 23 which is below the throttle valve and a second orifice 24 which is just above the throttle valve when the latter is closed. When the throttle is closed, the fuel line 2| to the nozzle I5 is closed by a needle valve 25, which is slidably mounted in a sleeve 26. This needle valve is secured to a stud 21, which extends through a slot 28 formed in the upper end of a link 29, the lower end of the link being pivotally connected to the end of a crank 30 secured to the throttle valve shaft IT. A lug 3| on, the needle valve stem is connected by a spring 32 to a lug 33 on the side of the mixing chamber housing, which holds the needle valve on its seat until, as the throttle is opened, the stud 21 is engaged by the lower end of the slot 28, the needle valve being then lifted against the resistance of the spring.

In the operation of the invention, enough fuel will be supplied through the holes 23 to idle the engine when the throttle is closed. As soon as thethrottle is opened a little, fuel is also fed through-the holes 24. The idle line 22 has an air bleed, as indicated at 34, so that considerable suction is required to draw fuel from the holes 23 or 24. Upon further opening of the throttle, as the vacuum in the vicinity of the jets drops to 12" or 14" of mercury, these jets cease to flow and most of the power charge is supplied through the nozzle I0.

As the lower end of the slot 28 engages the stud 21, theneedle valve or metering pin 25 is lifted from its seat and sufflcient fuel flows from the nozzle I5 to form a lean but ignitable mixture, while most of the power is derived from the bank of cylinders which are charged from the nozzle l0. Thus for intermediate power demands, the throttle is opened much wider, the compression is much higher and the engine operates much more efficiently than if a full charge were supplied to both banks of cylinders. fact, as the throttle is progressively opened and fuel ceases to fiow from the holes 23 and 24, a power charge will be supplied to'one bank of cylinders through the nozzle III, while no fuel at all is supplied to the other bank of cylinders until the lower end of the slot 28 engages and lifts the pin 25 and allows fuel to flow from the nozzle l5.

When full power is demanded, with the throttle wide open or nearly so, the needle valve or metering pin 25 is lifted high enough so that it ofiers no obstruction to the flow of fuel from the nozzle l5.

From the foregoing description, it will be seen that the invention permits the realization of all the advantages of a multi-cylinder high-powered engine in idling or in 'full power operation, and

permits operation at intermediate speeds and at light loads with the economy .of a smaller engine.

Obviously the invention may .be used with an engine having any number of cylinders, either straight or V type. The length of the slot 28 may be determined so that it will begin to lift the metering pin 25 at any desired point in the V throttling deviceincluding valves for the respective chambers, means for supplying like fuel charges to the respective chambers when the throttling device is in idling or wide open position and for supplying more fuel to one chamber than to the other when the throttling device isin an intermediate position.

2. In a charging device for multi-cylinder engines, two mixing chambers adapted to be connected to two different sets of cylinders, a throttling device including valves for the respective chambers, fuel jets of like capacity for supplying fuel to the respective chambers for idling and for power demand, and means for cutting down the flow through one of the power supply jets only when the throttling device is within a predetermined range between idling and full open position.

3. In a charging device for multi-cylinder engines, two mixing chambers adapted to be connected to two different sets of cylinders, a throttling device including valves for the respective chambers, fuel jets of like capacity to charge both chambers for idling, ducts of like capacity for supplying fuel charges to the two chambers for power, and throttle controlled means for cutting down the flow through one of said power supply ducts only when the throttling device is within a predetermined range between idling and full open position.

As a matter of 4, In a fuel charging device, two intake manifolds, each with a separate mixing chamber and same capacity for supplying fuel to the respective chambers, a metering pin associated with one of said fuel ducts only, andmeans operable from the throttle valve shaft to control said metering pin to restrict the flow of fuel through the duct associated therewith for predetermined throttle positions.

6. In a fuel charging device, two intake manifolds, each with a separate mixing chamber and a throttle valve, a commonshaft to which the throttle valves are secured, like means for supplying idling charges to the two manifolds when the throttle valves are closed or nearly closed, fuel ducts of like capacity for supplying fuel to the respective chambers as the throttle valves are opened wider, and means operable in conjunction with the throttle valve shaft to delay the full capacity operation of one of said ducts until the throttle valves are opened to a predetermined position.

7. In a fuel charging device, two intake manifolds, each with a separate mixing chamber and a throttle valve, a common shaft 'to which the throttle valves are secured, like means for supplying idling charges to the two manifolds when the throttle valves are closed or nearly closed, fuel ducts of like capacity for supplying fuel to the respective chambers as the throttle valves are opened wider, a metering pin associated with one of said fuel ducts only, and means operable in conjunction with the throttle valve shaft to control said metering pin to restrict the flow through theduct associated therewith, thereby delaying the full, capacity operation thereof, until the throttle valves are opened to a predetermined position.

8. In a charging device for multi-cylinder engines, two mixing chambers adapted to be con nected to two different sets of cylinders, a

throttling device including valves for the respective chambers, means for supplying like fuel charges to the respective chambers when .the throttling device is in idling or wide open position, and means to preclude any fuel supply to one of said chambers throughout an intermediate throttle range.

9. In a charging device for multi-cylinder engines, two intake passages adapted to be connected to two different sets of engine cylinders, a source of fuel supply leading to the two intake passages, throttling means for said passages operatable in idling, wide open, and intermediate positions, means to supply equal fuel mixture .charges to both of said passages when the throttling means is wide open, and means to cut off the fuel charge to one of said passages when the throttling means is in an intermediate position.

MARION MALLORY. 

